package com.yupi.springbootinit.utils;

import cn.hutool.core.collection.CollUtil;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.support.ExcelTypeEnum;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.web.multipart.MultipartFile;

import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * ClassName: ExcelUtils
 * Package: com.yupi.springbootinit.utils
 * Description: Excel相关工具类
 *
 * @Author lilray
 * @Create 2023/12/23 18:29
 * @Version 1.0
 */
@Slf4j
public class ExcelUtils {

        /**
         * excel 转 csv
         *
         * @param multipartFile
         * @return
         */
        public static String excelToCsv(MultipartFile multipartFile) {
//        File file = null;
//        try {
//            file = ResourceUtils.getFile("classpath:网站数据.xlsx");
//        } catch (FileNotFoundException e) {
//            e.printStackTrace();
//        }
                // 读取数据
                List<Map<Integer, String>> list = null;
                try {
                        list = EasyExcel.read(multipartFile.getInputStream())
                                .excelType(ExcelTypeEnum.XLSX)
                                .sheet()
                                .headRowNumber(0)
                                .doReadSync();
                } catch (IOException e) {
                        log.error("表格处理错误", e);
                }
                if (CollUtil.isEmpty(list)) {
                        return "";
                }
                // 转换为 csv
                StringBuilder stringBuilder = new StringBuilder();
                // 读取表头
                LinkedHashMap<Integer, String> headerMap = (LinkedHashMap) list.get(0);
                List<String> headerList = headerMap.values().stream().filter(ObjectUtils::isNotEmpty).collect(Collectors.toList());
                stringBuilder.append(StringUtils.join(headerList, ",")).append("\n");
                // 读取数据
                for (int i = 1; i < list.size(); i++) {
                        LinkedHashMap<Integer, String> dataMap = (LinkedHashMap) list.get(i);
                        List<String> dataList = dataMap.values().stream().filter(ObjectUtils::isNotEmpty).collect(Collectors.toList());
                        stringBuilder.append(StringUtils.join(dataList, ",")).append("\n");
                }
                return stringBuilder.toString();
        }

//        public static void main(String[] args) {
//                excelToCsv(null);
//        }
}
